A device that shields occupants from all possible forms of electronic intrusion and surveillance.

Molly wants to talk strategy with Case, but knows that near-universal surveillance can be achieved. How to have a private conversation?

[He] saw that it was a solid sandwich of circuitry, nearly a centimeter thick. He helped the man lift it and position it in the doorway. Quick, nicotine-stained fingers secured it with a white velcro border. A hidden exhaust fan began to purr.